Mine is based on word separators, and can be placed in a whd.py file and a installed in any folder inside the packages directory, e.g. /Packages/User. When saving a python script, you want to have the python console panel open so that you can see if there are any error messages -- usually caused by one or more lines needing a smaller or lager indent from the left-hand margin. Then you need a keymap assignment that calls the plugin, or you can compose a macro that calls the plugin. Mine is a newbie plugin that could be refined further by someone more experienced -- however, it does work.

I guess I misunderstood your workaround. I assumed that it was a fix for find_under_expand's behavior under the same name, i.e., I could drop it in and it would just work. I hadn't realized that it was defining a new command to use instead. Thanks for the clarification!